Sonia J. Vaida

A Randomized Controlled Trial Comparing the ProSeal™ Laryngeal Mask Airway with the Laryngeal Tube Suction in Mechanically Ventilated Patients

Background:The ProSeal™ Laryngeal Mask Airway (PLMA) (Laryngeal Mask Company, Henley-on-Thames, United Kingdom) is a new laryngeal mask with a modified cuff designed to improve its seal and a drain tube for gastric tube placement. Similarly, the Laryngeal Tube Suction (LTS) (VBM Medizintechnik Gmbh, Sulz a.N, Germany) is a new laryngeal tube that also has an additional channel for gastric tube placement. This study compared the placement and functions of these two devices. Methods:One hundred fifty patients undergoing general anesthesia for elective surgery were randomly allocated to the PLMA (n = 75) or LTS (n = 75). Oxygenation and ventilation, ease of insertion, fiberoptic view, oropharyngeal leak pressure, ventilatory data, ease of gastric tube insertion, and postoperative airway morbidity were determined. Results:After successful insertion of the devices in 96% of patients with the PLMA and in 94.4% with the LTS it was possible to maintain oxygenation, ventilation, and respiratory mechanics during the entire duration of surgery. Successful first and second attempt insertion rates were 57 patients (76%) and 15 patients (20%), respectively, for the PLMA and 60 patients (80%) and 11 patients (14.6%), respectively, for the LTS. Airway placement was unsuccessful with the PLMA in three patients and with the LTS in four patients. Time to achieve an effective airway was 36 ± 24 s with the PLMA versus 34 ± 25 s with the LTS. Gastric tube insertion was possible in 97.3% of patients with the PLMA and in 96% with the LTS. Conclusions:With respect to both physiologic and clinical function, the PLMA and LTS are similar and either device can be used to establish a safe and effective airway in mechanically ventilated anesthetized adult patients.

Postoperative outcome in high-risk infants undergoing herniorrhaphy: comparison between spinal and general anaesthesia

The incidence of inguinal hernia is higher in premature infants, particularly in low birth weight neonates. This latter group may also incur increased postoperative respiratory complications and inpatient admissions. The purpose of this study was to compare the effects of general and spinal anaesthesia on postoperative respiratory morbidity and on the length of hospital stay in high‐risk infants undergoing inguinal herniorrhaphy. Forty patients, all high‐risk infants who underwent unilateral or bilateral herniorrhaphies, were randomly assigned to receive general anaesthesia (n = 20) or spinal anaesthesia (n = 20). There was a significant difference in respiratory morbidity between the two groups, as well as a significant difference in the inpatient hospital stay. The present study suggests that spinal anaesthesia can be used safely for high‐risk infants, preterm or formerly preterm, undergoing inguinal hernia repair.

The Combitube in elective surgery: a report of 200 cases.

BackgroundThe Combitube has proved to be a valuable device for securing the airway in cases of difficult intubation. This study investigated the effectiveness of the Combitube in elective surgery during both mechanical and spontaneous ventilation. MethodsTwo hundred patients classified as American Society of Anesthesiologists physical status I and II, with normal airways, scheduled for elective surgery were randomly allocated into two groups: nonparalyzed, spontaneously breathing (n = 100); or paralyzed, mechanically ventilated (n = 100). After induction of general anesthesia and insertion of the Combitube, oxygen saturation, end-tidal carbon dioxide and isoflurane concentration, systolic and diastolic blood pressure and heart rate, as well as breath-by-breath spirometry data were obtained every 5 min. ResultsIn 97% of patients, it was possible to maintain oxygenation, ventilation, and respiratory mechanics, as well as hemodynamic stability during either mechanical or spontaneous ventilation for the entire duration of surgery. The duration of surgery was between 15 and 155 min. ConclusionsThe results of this study suggest that the Combitube is an effective and safe airway device for continued management of the airway in 97% of elective surgery cases.

Effects of peritonsillar infiltration on post-tonsillectomy pain. A double-blind study.

The concept that local infiltration of the operative area with a local anesthetic when using general anesthesia could alleviate postoperative pain is well known. We tested this concept on 129 patients scheduled for elective tonsillectomy. The patients were investigated in a double-blind, randomized study, and the operation was carried out via the standard technique of infiltrating the peritonsillar area preoperatively. The results indicated that preincisional infiltration of the tonsils with bupivacaine hydrochloride markedly decreased the intensity of pain following tonsillectomy, well beyond the immediate postoperative period.

A COMPARISON BETWEEN THE PLA COBRA AND THE LARYNGEAL MASK AIRWAY UNIQUE DURING SPONTANEOUS VENTILATION: A RANDOMIZED PROSPECTIVE STUDY

The Laryngeal Mask (LMA) Unique and the Cobra Perilaryngeal Airway (PLA) are single-use supraglottic devices. There are no published studies comparing these devices during spontaneous ventilation. We compared the LMA Unique and the Cobra PLA with respect to 1) ventilatory variables during spontaneous ventilation, 2) time to achieve an effective airway, 3) airway intervention requirements, 4) cuff seal pressures, 5) fiberoptic score, and 6) perioperative adverse events. Eighty adult ASA physical status I–II patients undergoing general anesthesia for minor routine surgery were randomly allocated to LMA Unique or PLA Cobra for airway management. No statistically significant differences were found between the devices with respect to inspiratory tidal volume, expiratory tidal volume, end-tidal CO2 concentration, respiratory rate, number and type of airway interventions required with placement, the fiberoptic score, and the incidence of perioperative adverse events. The oropharyngeal leak (seal) pressure was higher for the CobraPLA (27 ± 7 versus 21 ± 4 cm H2O; P < 0.001). The oxygen saturation was higher (98.1% ± 1% versus 97.3% ± 2%; P = 0.02) in the LMA group. Time of insertion was shorter for LMA (23.7 ± 2 s versus 26.6 ± 7 s; P = 0.02) and insertion difficulty was less for LMA (P = 0.03). As these differences were not judged to be clinically important, both devices appear to be effective in establishing an adequate airway in patients who are spontaneously breathing under general anesthesia.

An Evaluation of the Laryngeal Tube ® During General Anesthesia Using Mechanical Ventilation

The Laryngeal Tube® is a new supraglottic ventilatory device for airway management. It has been developed to secure a patent airway during either spontaneous or mechanical ventilation. In this study, we sought to determine the effectiveness of the Laryngeal Tube for primary airway management during routine surgery with mechanical ventilation. One-hundred-seventy-five subjects classified as ASA physical status I and II, scheduled for elective surgery, were included in the study. After the induction of general anesthesia and insertion of a Size 4 Laryngeal Tube, measurements of oxygen saturation, end-tidal CO2 and isoflurane concentration, and breath-by-breath spirometry data were obtained every 5 min throughout surgery. The lungs were ventilated with volume-controlled mechanical ventilation. The number of attempts taken to insert the Laryngeal Tube and the insertion time were recorded. In 96.6% of patients, it was possible to maintain oxygenation, ventilation, and respiratory mechanics by using mechanical ventilation throughout the surgical procedure. The results of this study suggest that the Laryngeal Tube is an effective and safe airway device for airway management in mechanically ventilated patients during elective surgery. IMPLICATIONS: In 96.6% of patients intubated with the Laryngeal Tube®, it was possible to maintain oxygenation, ventilation, and respiratory mechanics during mechanical ventilation.

Fiberoptic-guided Airway Exchange of the Esophageal-tracheal Combitube[registered sign] in Spontaneously Breathing Versus Mechanically Ventilated Patients

The aim of this study was to compare fiberoptic-guided airway exchange of the esophageal-tracheal Combitube[registered sign] (ETC, Kendall-Sheridan Catheter Corp., Argyle, NY) with an endotracheal tube in spontaneously breathing versus mechanically ventilated patients. Forty patients with Mallampati score III and IV scheduled for elective surgery were randomly allocated into two groups (n = 20 each): nonparalyzed, spontaneously breathing or paralyzed, mechanically ventilated patients. After anesthetic induction and insertion of the ETC, a fiberoptic bronchoscope threaded into an armored endotracheal tube was passed transnasally into the larynx. Endotracheal intubation was successful in 18 spontaneously breathing patients and in 15 patients during controlled ventilation. Successful airway exchange was completed in significantly less time (P < 0.05) in spontaneously breathing patients (9 +/- 3 min; mean +/- SD) than in mechanically ventilated patients (13 +/- 4 min). Both methods allowed for continuous airway control and maintenance of ventilation and oxygenation. The described method is a means of replacing the ETC with an endotracheal tube without interruption of airway control or ventilation. Replacing the ETC with an endotracheal tube using this method is more readily accomplished during spontaneous ventilation than during controlled ventilation. Implications: We describe the replacement of the Combitube[registered sign] by an endotracheal tube by the aid of fiberoptic bronchoscopy and without interruption of airway control or ventilation. The performance of this technique was facilitated by spontaneous ventilation compared with mechanical ventilation. (Anesth Analg 1999;88:193-6)

Successful use of argatroban during the third trimester of pregnancy: case report and review of the literature.

Direct thrombin inhibitors are commonly used anticoagulants in patients with known or suspected heparin‐induced thrombocytopenia (HIT). All three direct thrombin inhibitors available in the United States—argatroban, bivalirudin, and lepirudin—are pregnancy category B drugs based on animal studies, but little data are available on the safety of these agents during human pregnancy. Whereas several case reports support the safe use of lepirudin, only one case report has been published with argatroban and none with bivalirudin. We describe a 26‐year‐old pregnant woman with portal vein thrombosis and thrombocytopenia treated with argatroban for possible HIT during her last trimester. An argatroban infusion was started at 2 μg/kg/minute during her 33rd week of pregnancy, with the dosage titrated based on the activated partial thromboplastin time; infusion rates ranged from 2–8 μg/kg/minute. Treatment continued until her 39th week of pregnancy, when labor was induced. Argatroban therapy was discontinued 7 hours before epidural anesthesia. The patient successfully delivered a healthy male newborn, devoid of any known adverse effects from argatroban. The infant was found to have a small ventricular septal defect and patent foramen ovale at birth, but it is unlikely that these were caused by argatroban since organogenesis occurs in the first trimester. Even though the cause of this patients thrombocytopenia was later determined to be idiopathic thrombocytopenic purpura, this is an important case that adds to the literature on use of argatroban during pregnancy.

The effectiveness and safety of spinal anaesthesia in the pyloromyotomy procedure

Background: Hypertrophic pyloric stenosis is a relatively common disorder of the gastrointestinal tract in infancy, causing projectile vomiting and metabolic abnormalities. Surgical management in the form of pyloromyotomy under general anaesthesia has been reported as safe for relieving the obstructed bowel. A number of studies have demonstrated the advantages of spinal anaesthesia over general anaesthesia in high risk infants undergoing minor infraumbilical surgery. The purpose of this study was to evaluate spinal anaesthesia as an alternative option to general anaesthesia in infants undergoing pyloromyotomy.

The influence of preemptive spinal anesthesia on postoperative pain

STUDY OBJECTIVE To examine the influence of spinal anesthesia on postoperative pain and postoperative opioid requirements. DESIGN Prospective randomized study. SETTING Bnai-Zion Medical Center, Haifa, Israel-a government hospital. MEASUREMENTS AND MAIN RESULTS 30 ASA physical status I and II unpremedicated women undergoing elective total abdominal hysterectomy were randomly allocated into two groups of 15 patients each using a sealed envelope technique. Patients in Group 1 were given a subarachnoid injection of 12 mg hyperbaric bupivacaine and after 10 minutes general anesthesia was induced. Patients in Group 2 received only general anesthesia. Anesthesia was induced with midazolam and maintained with oxygen, N2O, isoflurane, and pancuronium. No opioids were given intraoperatively. Postoperatively patient-controlled analgesia (PCA) with morphine was initiated in both groups (1 mg x mL(-1), bolus dose 1 mg, lockout interval 10 minutes, and background infusion 1 mg x mL(-1)) at patient first request for analgesic. Pain was assessed over 24 hours by cumulative morphine dose and visual analog score (VAS). Postoperative PCA morphine consumption at 2, 6, and 24 hours following patient first request for analgesic for Groups 1 and 2 were: 3.1 +/- 1 mg versus 7.2 +/- 3 mg (p = 0.04), 13.4 +/- 2 mg versus 17.2 +/- 4 mg (p = 0.03) and 35.9 +/- 8 mg versus 47.7 +/- 8 mg in Group 2 (p = 0.04). VAS scores at 4, 6, 12, and 24 hours postoperatively were not significantly different between the two groups. CONCLUSIONS Preoperative neural blockade may reduce postoperative analgesic requirements.